Chair

ABSTRACT

An adjustable arm chair has a chair body including a stiff tubshaped back rest portion, a stiff tub-shaped leg portion, and a flexible substantially flat seat portion connecting the back rest portion and the leg portion; and a support construction for the chair body for continuous adjustment of the back rest portion, the seat portion and the leg portion relative to one another and to the support construction, so that the chair can be tilted forwardly and rearwardly in a continuous stepless manner into any desirable rest or upright positions, when the user shifts his body weight in the chair, without requiring the provision of separate adjustment means of any kind.

United States Patent Mehbert et al. Apr. 1, 1975 1 CHAIR 3.343.8709/1967 Thatcher 297/457 9, 7 L 297 457 1751 Klaus m mvale-m, 3.239.195.3133; 6555551, 2975457 both of Stuttgart, Germany 3.771.583 11/1973Bottemiller 297/445 x ig B I Bofinger, nsfeld Sellner Germany PrimaryExaminer-Francis K. Zugel i973 Attorney, Agent, or Firm-Michael S.Striker [21] Appi. No: 340,824

[57] ABSTRACT [30] Foreign Application Priority Data An adjustable armchair has a chair body including a May 10, i972 Germany .9 2222840 stifftub-shaped back rest portion, a stiff tub-shaped leg portion, and aflexible substantially flat seat por- [52] US. Cl. 297/320, 297/457 tionconnecting the back rest portion and the leg por- [5 l Int. Cl. A4761/033 tion; and a support construction for the chair body for Fitld ofstarch 7/3 457, continuous adjustment of the back rest portion, the

4l9 seat portion and the leg portion relative to one another and to thesupport construction, so that the [56] References Cited chair can betilted forwardly and rearwardly in a con- UNITED STATES PATENTS tinuousstepless manner into any desirable rest or up- 2324318 7/1943Nicdringhaus 297/457 x Q I W Shifts Y weight in 1454;) H1943 Cunningham,297/419 x the chan without requmng the prov1s1on of separate 2.51139334/1950 Brcucr 297 445 x adjustment means of any kind.

2.602.49l 7/1952 Rakafunsky r r r 297/4l9 X 2.745.468 5/1956 Kramer297/457 4 Clfllmsr 6 Drawlng CHAIR BACKGROUND OF THE INVENTION Thepresent invention relates generally to a chair, and more particularly toan upholstered arm chair having a chair body and support means.

It is already known in the art to provide arm chairs or the like. whichcan be tilted from a more or less upright position to a more or lessinclined rest position and back again to an upright position by means ofan adjustment system consisting of levers, bars, rod and/or the like.The construction of such an adjustment system naturally is difficult andexpensive. In addition, such an adjustment system usually makes thechair bulky and clumsy.

SUMMARY OF THE INVENTION It is, accordingly, an object of the presentinvention to provide an improved adjustable or tiltablc chair. such asan upholstered arm chair or the like, which does not have the foregoingdisadvantages.

More particularly it is an object of the present invention to provide achair which can be tilted from a substantially upright position to asubstantially inclined rest position in a continuous manner, without anysteps and without any special separate adjusting means.

Still a further object of the present invention is to provide a chairwhich can be tilted from a substantial upright position to any inclinedrest position in a continuous manner and raised again to said uprightposition, when the user shifts the weight of his body in the chair.backwardly and forwardly, respectively.

In pursuance of the foregoing objects, and others which will becomeapparent hereafter, a novel adjustable chair has been developed which,briefly stated, comprises a chair body including a back rest portion, aleg portion and a seat portion connecting the back rest portion and theleg portion. and support means to support the chair body for continuousadjustment of the back rest. seat and leg portions relative to oneanother and relative to the support means. The back rest portion and theleg portion can be made nonyielding and stiff while the seat portion ismade flexible according to one currently preferred embodiment of thepresent invention.

The design of the novel chair. its chair body and its support meansallows the user to adjust the chair from a substantially uprightposition to a more or less inclined rest position in a continuousstepless manner and vice versa. without any separate adjustment meansand without any levers. rods or bar or the like. He only shifts ordisplaces his body weight forwardly or backwttrdly, e.g. by bending orstretching his legs or bending the upper portion of his body forward. Hethus is able to select any stable intermediate position between thesubstantially upright and an extreme inclined rest position.

The back rest portion and the leg portion are preferably substantiallytubor trough-shapcd, whereas the transverse cross-section of the seatportion is substantially flat. However. the shape of the seat portion ina direction intermediate the back rest portion and the leg portionpreferably is part circular at least when the chair is not used. Thelength of the part-circular outline in this direction preferably isbetween approximately l2 and I8 cm.

The chair body is preferably supported by the support means in one areabetween the seat portion and the leg portion and in another area in thatregion of the back rest portion which is adjacent the seat portion. Thechair body and the support means are preferably connected in thefirstntentioned area by means of two brackets fastened to said areaunder the chair body, rotatable on a transversely extending shaft heldby two forwardly disposed legs of the support means; and in the secondarea by means of a strap extending transverscly under the chair body andnormal to a line intermediate the back rest portion and the leg portion,and two arm rests, suspended from two studs, which are transverselyspaced parts of the strap, and from two hand supports, which areintegral parts of two rearwardly placed legs of the support means.

The arm rests are preferably made of a flexible material, leather,artificial leather. a textile fabric or the like. They preferablyconsist of endless, loop-shaped bands, suspended front the studs of thestrap and from studs on the hand supports. respectively.

The brackets of the forwardly disposed connecting means may each consistof two angularly spaced bars and spacing means, such as a screw.extending through two bars, so that the frictional forces between thebrackets and the shaft hold by the two forwardly disposed legs of thesupport means can be adjusted.

The contact points between the chair body and the two brackets,rotatable on the shaft, preferably are locatcd rearwardly of a verticalplane which includes the axis of the shaft, so that the two brackets canpivot rearwardly about the shaft, when the chair is used and the usershifts his body weight forwardly.

The shaft holding the brackets may be secured on the two forwardlydisposed legs of the support means by means of adapter bushes, and thebrackets may be held in place by spacer sleeves on the shaft.

The chair body can be made of an ABS-polymerization product of the like.The thickness ofthe body chair can amount to between approximately 2.5and 5 mm.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself. however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a side-elevational view of achair according to the present invention.

FIG. 2 is a part-sectional exploded view of a detail of the chair inFIG. 1;

FIG. 3 is a cross-section of a detail of the chair in FIG. I;

FIG. 4 is a cross-section of a further detail, taken on the line IVIV ofFIG. 4;

FIG. 5 is a fragmentary top view of a portion of the chair in FIG. 1;

FIG. 6 is a cross-section taken on line Vl\/I of FIG.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments in the drawingwill now be discussed. It will be seen that the adjustable arm chair I0(FIG. ll comprises a support means 12 which is made of metal. such asextruded aluminum. or of other suitable materials. such as syntheticplastic materials or wood. The support means 12 can comprise a base 22.two forwardly disposed but rearwardly inclined legs 16 and tworearwardly disposed but forwardly inclined legs 18. Legs 18 are. as isevident from the drawing. longer than legs 16 and are provided withhorizontally and forwardly disposed hand supports 20 which are integralparts of legs 18. The forward ends of hand sup ports 20 are shaped astwo rings 24 (sec especially HO. 4). through which studs 26 areinserted. Arm rests 28 and 34 (FIGS. 1 and 5) run around studs 26 andhetween the two rings 24 respectively. The arm rests 28 and 34preferably are flexibly. endless. loop-shaped hands. made of leather.artificial leather. a plastic material. a textile fabric. or the like.The free end of cach leg 16 of support means 12 is shaped as a ring 42with bore 44. in which bores 44 legs [6 hold end portions 46 of atube-shaped shaft 48 (FlG. 2).

The chair ofthe present invention comprises. in addition to the supportmeans. the chair body and the upholstering. two foot portions 22. twoforward legs [6. two rear legs 18 and two hand supports 20. whichelements are laterally disposed in relation to each other. respectively.along lines and planes normal to the draw: ing plane of FIG. I. Thechair body I4 is disposed between and supported by these clement pairs,which will he discussed in more detail in the following.

Shaft 48 (FIG. 3) connects the end portions of the two legs l6. Endportions 46 (FIG. 2) of shaft 48 are inserted in bores 44 of rings 42and held by the legs l6 lFlG. I). End portions 46 can for example heprovided with two axially extending slits 50 PK]. 2), so that endportions 46 can he expanded outwardly and pressed against the innerwalls of bore 44. Adapter bushes 52 for each end portion 46 ofshaft 48are provided for this purpose. Adapter hushes 52 can for example havefour axially extending equi-angularly arranged slits S4. Adapter bushes52 also have an inner hore with an inner thread 58 and a conicalenlargement 59. When supporting means 12 and the connecting meansbetween supporting means [2 and chair body 14 are assembled. adapterbushes 52 are inserted in the end portions of shaft 48. and two screws56 having conical heads are screwed into the threads 58 of adapterbushes 52. whereby portions SI of the adapter hushes 52 are pressedoutwardly and radially against the inner walls of end portions 46 ofshaft 48. so that portions of end portions 46 are pressed outwardly andsuhstan' tially radially against the inner walls of bore 44. and so thatshaft 48 is firmly held in the rings 42 of legs [6.

(hair hotly l4 can he made of an ABS-polymerization product. e.g. by avacuum process within the skill of those conversant with the art. Othersynthetic plastic materials. cg. polyamides. can also he used for theproduction of the chair body. and other manufacturing or productionprocesses. eg extrusion processes, can he resorted to. Suitableupholstering can he provided. fastened if so desired. to the chair hodyl4. as is indicated by a dotted line in FlG. I. it extends alongsubstantially the hole length of chair hotly l4. A support for the hackof the neck can also he provided. which can be fastened to or suspendedfrom the chair body itself. iii to or from the upholstery Chair body l4consists ofone substantially nonyiclding and stiff back rest portion 80.one sub tantially noir (ill yielding and stiff leg portion 82. and oneflexible. elastic seat portion 84. The three portions form the integralchair body 14. Seat portion 84 is the connecting link between back restportion 80 and leg portion 82. Back rest portion 80 and leg portion 82have. as is illustrated in FlG. 6. schematically and in eross-section.substan tially the shape of a tub or a trough with an arcuately shapedmain part 81. laterally disposed ribs 83. and edge portions 85. whichlatter extend in a plane which is substantially normal to the plane oflateral ribs 83. The nonyielding and stiffness properties of back restportion 80 and leg portion 82 are obtained mainly as a consequence ofthe arcuate or tuh-shape of main part 81 ofthese portions 80 and 82.However. lateral ribs 83 contribute of course also to these properties.The up holstery can also contribute substantially to such properties ofthe chair body.

Seat portion 84 is shaped substantially as a part of a cylinder. Across-section of seat portion 84 in a plane normal to the drawing planeof FIG. I will show that seat portion 84 is substantially flat along aline normal to a line intermediate the back rest portion 80 and legportion 82. The stiff back rest portion 80 and the stiff leg portion 82change into the flexible seat portion 84 in the areas 86 and 88respectively. and seat portion 84 thus constitutes an elastic orflexible joint or link be' tween the back rest and the leg portions. Aslight arching of seat portion 84 in transverse direction is admissihlein order to better hold the upholstery. The llcxibility and elasticityis not substantially impaired by such a measure.

Chair body [4 is held by support means l2 in two ar' eas. Strap 36 isarranged in the lower third region of back rest portion 80 (FIG. 5). Itis extended along a substantially horizontal line normal to a lineintermediate back rest portion 80 and leg portion 82 and encirclestub-shapcd part 81 of back rest portion 80. Strap 36 can, as isillustrated in FIG. 5, he provided with projections 38 facing andfastened to part 8] on the outer wall of back rest portion 80. forinstance with screws. Strap 36 is also provided with studs 30 on each ofits lateral portions. as is depicted in FIG. 5. Studs 30 can be integralparts of strap 36 and be extended along a line normal to a lineintermediate the back rest portion 80 and the leg portion 82.

The flexible arm rests 28 and 34. described above. which consist ofendless loop-shaped bands. the forward end portions of which run aroundstuds 26 and are held by these studs. also run around and held by studs30 of strap 36 (the rearward end portions of the bands). Thus. arm rests28 and 34 are holding the strap 36. Studs 30 are suspended or insertedin the rearwardly extended loops of arm rests 28 and 34 for thispurpose. To prevent the loops from sliding off studs 30. the latter canhe provided with beads having a larger diameter than the diameter of therest of the stud body and being placed on the front end portions ofthestuds. Other means, eg. suitable stops, can of course he used for thispurpose.

The second support area for chair hody I4 is located in the regionbetween seat portion 84 and leg portion 82. Body portion of chair bodyl4 (FIG. 3) is provided with a downwardly directed tuh-shaped cavity 72in this area. Shaft 48 holds two laterally disposed brackets 60. whichpreferably can he made of an elastic synthetic material. although othermaterials such as metals and wood can he used.

FIG. 3 is a cross-section of one of brackets 60 showing a bore 68extending in the same direction as the direction ofshaft 48. Bore 68surrounds shaft 48. Bracket 60 consists of two bars 62 and 64. angularlyseparated from each other by a slit 65. A bore 66 extends in a directionnormal to the direction of bore 68 and through the two bars 62 and 64.The two brackets 60 are. as illustrated in FIGS. l and 3. fastened byscrews to chair body I4 or rather to the downwardly directed tubshapedcavity 72 ofchair body I4. Triangular blocks 74 are used to fastenbrackets 60 to the inner wall ofcavity 72. Blocks 74 can preferably bemade of the same material as brackets 60 and have a width which is thesame as the width of brackets 60. e.g. between approximately 4 and 6 cm.This is of course not a necessary dimensional limitation. brackets 60and blocks 74 can have any desired width in lateral direction.

FIG. 3 shows how block 74 is fastened to legs 62 and 64 of bracket 60 bymeans of screws 76 and 78 through the body of cavity 72. The profile ofblock 74 preferably is the same as the profile of cavity 72 to conformto the latter so that as large as possible bearing area between block 74and the body of cavity 72 can be ob tained.

FIG. I shows that the center line of brackets 60 is tilted rearwardlyand counterclockwise at an angle a relative to a vertical line throughthe axis of shaft 48. This angle varies as the position of the chairbody va ries. The arrangement is however so balanced that the centerline of brackets 60 is always tilted rearwardly, never forwardly. forall possible positions of the chair body. Angle a can for instance bewhen the chair is not used.

The mode of operation of the novel chair is as follows: II' a personpositions himself in the chair in a normal sitting position. leg portion82 of the chair body will extend forwardly in a substantial horizontaldirection. whereas back rest portion 80 will be inclined rearwardly. butonly to a small degree (FIG. I and support the back of the user. Thearms of the user are supported by flexible arm rests 28 and 34. Thesteeper the sitting position is. the larger is the angle a.

If the user now leans rearwardly and/or more or less straightens out hislegs at the same time. the back rest portion 80 will tilt in a rearwarddirection. and the brackets will turn in a clockwise manner. The angle abetween the center line of brackets 60 and the vertical line through theaxis of shaft 48 will grow smaller. Leg portion 82 will be tilted moreor less downwardly from its previous substantially horilontal position.Seat portion 84 which has a part-circular outline in the uprightposition will be flatter when the chair body is thus tilted rearwardlyand counterclockwise. Studs 30 of strap 36 which supports back restportion 80 follow. when back rest portion 80 is tilted rearwardly anddownwardly. a circular line around a point 90. which is the point ofintersection between legs l8 and hand supports 20. re spectively. Armrests 28 and 34 remain stretched but are now stretched downwardly frompoint 90.

When the user raises his body forwardly and/or bends his legs. back restportion 80 returns to a more or less upright or sleep position. whereasleg portion 82 returns to a more or less horizontal position from itsdownwardly inclined position. When the user raises his body from atilted rest position to an upright sitting position. brackets 60 rotaterearwardly and downwardly around shaft 48. namely counterclockwise, inFIG. I.

(ill

All positions of the chair body [4. between an extreme upright positionand an extreme rest position are stable. The tub'shaped design of backrest portion and leg portion 82 give these portions the necessarystiffness and nonyielding characteristics. whereas seat portion 84functions as a flexible joint or link between the two stiff andnonyielding portions 80 and 82 due to its substantially flatcross-section in a plane normal to a line intermediate back rest portion80 and leg portion 82.

The various possible upright. rest and lying positions can be reached bya simple shifting or displacement of the body weight of the user. cg. bythraightening out. pulling up or bending his legs and/or by more or lessstrong bending or inclination of the upper portion of his body.

The following dimensions for the various elements of the support meansofthe chair of the present invention have proven to be suitable for awell-balanced arrangement, although they are to be considered as beingexemplary only. The center of shaft 48 has been taken as a referencepoint.

The point of intersection between leg 18 and hand support 20. namelypoint 90. around which arm rests 28 and 34 can rotate. located forinstance between approximately 30 and 35 cm over the reference point andbetween approximately 5 and 8 cm behind the reference point. The centerpoint of stands 30 of strap 36 is located. when the chair is not used.between approximately 23 and 28 cm over the reference point. whereas thelength of arm rests 28 and 34 between point and the center point ofstuds 30 is between approximately 30 and 33 cm. The length of theflexible seat portion 84 along its outer curvature. is betweenapproximately 12 and I8 cm, preferably l5 cm. when the chair is used.whereas it is between I] and 15 cm, when the chair is not used.

The larger the angle between the bars 62 and 64 of brackets 60 is, themore braking action between the chair body and the shaft of the supportmeans can be achieved. Thus. the ease or difficulty with which the chairbody can be tilted or lifted into various positions can be readilyadjusted by increasing or decreasing the angle between bars 62 and 64 ofbrackets 60 by means of screws in bores 66.

The chair of the present invention can be tilted or lifted in acontinuous stepless manner into any of the rest or upright positions ifthe user shifts or displaces his body weight in various ways and noseparate adjust ment means of any sort are required.

While the invention has been illustrated and described as embodied in anadjustable arm chair with up bolstering. it is not intended to belimited to the details shown. since various modifications and structuralchanges may be made without departing in any way from the spirit of thepresent invention.

Without further analysis. the foregoing will so fully reveal the gist ofthe present invention that others can by applying current knowledgereadily adapt it for various applications without omitting features thatfrom the standpoint of prior art fairly constitute essentialcharacteristics of the generic or specific aspects of this inventionand. therefore. such adaptations should and are intended to becomprehended within the meaning and range of equivalence of thefollowing claims.

What is claimed as new and desired to be protected by Letters Patent isset forth in the appended claims:

l. A chair. especially an armchair, comprising a chair bod including arigid backrest portion, a rigid leg por' tion. and a flexible seatportion connecting said backrest portion and said leg portion so thatsaid backrest portion and said leg portion are pivot-able forward andbackward about and with reference to said seat por tion; and supportmeans including rearward legs and supporting said chair body forcontinuous adjustment of the position of said portions relative to oneanother and to said support means. at the will of a user, said supportmeans comprising connecting means between said chair body and saidsupport means, in one area be tween said seat portion and said legportion and in another area in that region of said back rest portionwhich is adjacent said seat portion, said connecting means in said otherarea comprising a strap extending in a direcfill tion substantiallynormal to a line intermediate said hack rest and leg portion twolaterally disposed studs on said strap extending in a directionsubstantially normal to said line and two arm rests said arm res sconnecting said rearward legs and said studs respectively 2. A chair asdefined in claim I. wherein said rearward legs are provided with handsupports, to which said arm rests are connected.

3. A chair as defined in claim I, wherein said arm rests consist offlexible, endless, loop-shaped bands, made of a material selected fromthe group composed of leather. artificial leather. and textile fabrics.

4. A chair as defined in claim 3. wherein said bands are suspended fromsaid studs of said strap and said hand supports of said rearward legs.respectively

1. A chair, especially an armchair, comprising a chair body including arigid backrest portion, a rigid leg portion, and a flexible seat portionconnecting said backrest portion and said leg portion so that saidbackrest portion and said leg portion are pivotable forward and backwardabout and with reference to said seat portion; and support meansincluding rearward legs and supporting said chair body for continuousadjustment of the position of said portions relative to one another andto said support means, at the will of a user, said support meanscomprising connecting means between said chair body and said supportmeans, in one area between said seat portion and said leg portion and inanother area in that region of said back rest portion which is adjacentsaid seat portion, said connecting means in said other area comprising astrap extending in a direction substantially normal to a lineintermediate said back rest and leg portion, two laterally disposedstuds on said strap extending in a direction substantially normal tosaid line, and two arm rests, said arm rests connecting said rearwardlegs and said studs, respectively.
 2. A chair as defined in claim 1,wherein said rearward legs are provided with hand supports, to whichsaid arm rests are connected.
 3. A chair as defined in claim 1, whereinsaid arm rests consist of flexible, endless, loop-shaped bands, made ofa material selected from the group composed of leather, artificialleather, and textile fabrics.
 4. A chair as defined in claim 3, whereinsaid bands are suspended from said studs of said strap and said handsupports of said rearward legs, respectively.